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Pioneering IP Services Provider, Exario Networks, Deploys Comprehensive Sonus and BroadSoft Solution to Deliver Enhanced Voice Services to Enterprise Customers

WESTFORD, Mass., and GAITHERSBURG, Md., July 17, 2001 – Sonus Networks (Nasdaq: SONS), a leading provider of voice infrastructure solutions for the new public network, and BroadSoft, Inc., the leading provider of carrier-class service delivery systems for packet-based enhanced telephony services, announced today that BroadSoft has attained Platinum Partner standing in Sonus' Open Services Partner Alliance (OSPA). 

BroadSoft is one of the first companies to meet all of the criteria to become a Sonus Platinum partner. To attain Platinum status, companies must have products and applications complementary to Sonus' product family and achieve Powered status by successfully completing interoperability testing in the OSPA Interoperability Lab. Most importantly, Sonus Platinum partners' solutions must be deployed in a live service provider network together with a Sonus product. Exario Networks, a leading provider of outsourced IP services based in Parsippany, New Jersey, has implemented the Sonus/BroadSoft solution to deliver converged voice and data private IP solutions to its enterprise customers.

By deploying Sonus' voice infrastructure solutions, including the GSX9000 Open Services Switch and the PSX6000 SoftSwitch and the BroadSoft BroadWorks service delivery system to augment its existing Class 4 IP tandem nationwide network, Exario has expanded its voice offerings to the enterprise market to provide an enhanced suite of advanced IP network solutions. Exario has also integrated an extensive set of web-enabled enhanced telephony services into its proprietary web-based network management platform, the Exario virtualNOC, including conferencing, call forwarding, voice mail, follow-me-anywhere calling, and auto attendant.

"Leveraging the power of the easy-to-use, flexible BroadWorks service delivery system coupled with the unparalleled quality of Sonus' voice infrastructure products, allows us to differentiate our service offerings and stay ahead of the competition," said Tom Mizzone, CEO of Exario Networks. "The real value of this partnership is that it creates one of the most comprehensive suites of converged services available today and gives Exario's customers more choices in the services they buy, provision and manage. We view our relationship with these two companies as a key component of our next-generation network strategy."

Sonus provides a complete packet voice solution that has been designed to carrier standards, delivering toll-quality voice, system redundancy, and the capacity to handle extremely large call volumes. Additionally, Sonus' award-winning voice infrastructure solutions offer a single platform that allows carriers to deliver a range of communications services including traditional long distance and local voice services, wholesale voice services, and enhanced services, such as unified communications, presence management, enhanced voicemail, voice portals and many others. 

BroadSoft's flagship product, BroadWorks, is the industry's first comprehensive enhanced service delivery system for packet-based business services. BroadWorks enables service providers to rapidly enter new markets and immediately generate new revenues with easy-to-use, differentiated local exchange services over packet-based networks as well as the traditional public switched telephone network (PSTN). BroadWorks includes a rich set of business options such as call waiting, voicemail, conferencing, auto-attendant and follow-me-anywhere services, and can interoperate with other network elements and business applications for a comprehensive set of integrated services without lengthy and expensive proprietary development. By installing BroadSoft's BroadWorks service delivery system in conjunction with Sonus solutions, carrier customers gain unprecedented flexibility and lower costs as they strive to offer innovative, customized, enhanced services to their business customers.

"We are pleased that BroadSoft has met our Platinum Partner requirements and we are excited that our combined solution is operating today in Exario's revenue-generating network," said Terri Griffin, vice president of marketing programs at Sonus Networks. "Attaining interoperability with leading vendors such as BroadSoft is fundamental to the proliferation of next-generation voice solutions."

"BroadSoft is proud to be one of the first Sonus Powered companies to attain Platinum Partner status," said Scott Wharton, vice president of marketing for BroadSoft. "By making BroadWorks fully interoperable with Sonus' industry-leading packet voice solutions, our companies are bringing a tremendous market advantage to carriers through superior technology solutions and service differentiation."

BroadSoft first attained Sonus Powered status in August 2000, after BroadSoft submitted its service delivery and call routing system to Sonus' Interoperability Laboratory, where interoperability with Sonus' equipment was demonstrated through a series of tests. In order to attain Sonus' Platinum Partner status, BroadSoft had to fulfill a number of key requirements including: being commercially deployed in a carrier's network interoperating with Sonus products; proving carrier-class reliability and scalability; possessing resources to support 24x7 technical support; and offering sales, marketing, and technical resources to support large carrier deployments.

About BroadSoft

BroadSoft, Inc., is the leading provider of service delivery systems for next-generation telephony services. BroadWorks, the company's flagship product, allows service providers to rapidly and economically design and deploy web-enabled enhanced telephony services to their customers. BroadSoft has received extensive industry recognition including recognition as a "Hot Start-Up" by America's Network and Telecommunications magazines, two of the leading telecommunications industry publications. BroadWorks was also recognized as Product of the Year by Communications Solutions magazine. BroadSoft is located near Washington, DC, in Gaithersburg, Maryland, and also maintains a research and development facility in Montreal, Canada. Additional information can be found at www.broadsoft.com.

About Sonus Networks

Sonus Networks, Inc. is a leading provider of voice infrastructure products for the new public network. Sonus' solutions enable service providers to deploy an integrated network capable of carrying both voice and data traffic, and to deliver a range of innovative, new services. The Sonus Open Services Architecture (OSA) and award-winning Packet Telephony suite cut the time-to-market for competitive new service products, allowing carriers and third-party developers to expand market share and build important new revenue streams. Its highly scalable products fully interoperate with and extend the life and utility of today's public network. Sonus embodies in its management and staff decades of experience in developing carrier-class voice, data and multimedia solutions for implementation in the world's largest networks. Sonus, founded in 1997, is headquartered in Westford, Massachusetts. Additional information on Sonus is available at http://www.sonusnet.com.

This release may contain projections or other forward-looking statements regarding future events or the future financial performance of Sonus that involve risks and uncertainties. Readers are cautioned that these forward-looking statements are only predictions and may differ materially from actual future events or results. Readers are referred to Sonus' Quarterly Report on Form 10-Q, dated May 14, 2001, filed with the SEC, which identifies important risk factors that could cause actual results to differ from those contained in the forward-looking statements. These risk factors include, among others, the Company's ability to grow its customer base, dependence on new product offerings, market acceptance of its products, integration risks relative to its acquisition of telecom technologies, rapid technological and market change and manufacturing and sourcing risks.

Open Services Partner Alliance, GSX9000, PSX6000 and Open Services Architecture are trademarks of Sonus Networks. BroadSoft and BroadWorks are trademarks of BroadSoft, Inc. All other company and product names may be trademarks of the respective companies with which they are associated.